Fluid-tight closure means



Jan. 18, 1944. H. w. DODSON FLUID- TIGHT CLOSURE MEANS Filed Sept. 18,1940 2 Sheets -Sheet l INVENTOR. j iowdrz? H-DOJS'OIL 4:7TORNEY.

Jan. 18, 1944. H. w. DODSON FLUID TIGHT CLOSURE MEANS Filed Sept. 18;1940 2 Sheets-Sheet 2 INVENTOR. HbwOJZYDZ DOJJOH w 7 92 5 m 2 zwwl 1 W 6z 3 4 l MZHH gm. 4 9 R v 5. H\ M m mm I 3% 1 4 5 J ma 1 3w 0 1 PatentedJan. 18, 1944 FLUID-TIGHT CLOSURE MEANS Howard W. Dodson, Aidan, Pa.,assignor by mesne assignments, to United Steel Barrel Company,Philadelphia, Pa., a corporation of Pennsylvania Application September18, 1940, Serial No. 357,205

4 Claims.

The present invention relates to certain new and useful closure meansfor the openings of metallic containers, such as steel drums, barrels,tanks or the like.

For th purpose of illustrating the invention, there isshown in theaccompanying drawings forms thereof which are at present preferred,since the samehave been found in practice to give satisfactory andreliable results, although it is to be understood that the variousinstrumentalities of which the invention consists can be variouslyarranged and organized and that the invention is not limited to theprecise arrangements and organizations of the instrumentalities asherein shown and described.

In the accompanying drawings, wherein like reference characters indicatelik parts.

Figure 1 represents an enlarged fragmentary sectional perspective viewshowing the inwardlyextending flanged body metal portion of oneembodiment of the present invention, shown prior to the casting of abushing therearound.

Figure 2 represents a view showing the inwardly-extending flanged bodymetal portion enveloped by the bushing which has been cast in situtherearound.

Figure 3 represents an enlarged view, partly in section and partly inelevation, showing the assembled closure means, with the closure-plugportion thereof being wire-sealed for tamper-indicating purposes.

Figure 4 represents a view similar to that shown in Figure 3, butshowing the closure-plug provided with alternative tamper-indicatingmeans,

comprising a relatively rotatable thin sheet-metal seal cap secured tothe plug.

Figure 5 represents, on a much reduced scale, a. perspective viewlooking down at the top end of a cylindrical container having closuremeans constructed in accordance with the present invention.

Figure 6 represents a fragmentary enlarged sectional view taken on line5--6 of Figure 5.

In the embodiments of the present invention illustrated in Figures 1 to4, inclusive. th numeral l0 represents the wall of a sheet metalcontainer in the vicinity of an opening I I, through which opening thecontainer may be filled or emptied. This opening I I may be formed onany desired portion of the container, as for example on an end Wall ofthe container, or on a flat or cylindrical side wall thereof, or thelike.

Referring now more particularly to Figure 1, the body metal of thecontainer wall In in the vicinity of the opening H is flanged inwardlyrelative to the container to provide an inwardlyextending integralgenerally cylindrical flange portion l2 bordering the opening. A seriesof anti-rotational, preferably well-defined, projections l3 integralwith the flange l2 may be provided at suitable intervals along theinnermost edge of said flange for the purpose of providing keying orgripping surfaces which will prevent rotation or loosening of die-castbushing H, which is subsequently cast in situ around the body metalflange [2. These keying projections i3 may be transversely bent into aplane inter secting the axis of the opening, as for example radiallyinwardly as illustrated in Figure 1, thereby further to prevent axialmovement of the subsequently cast-ln-situ bushing [4 relative to.

the body metal flange l2.

Flange portion I2 and its associated anti-rotational projections l3 maybe formed in any suitable manner, as for example by being drawn or bentinto their desired ultimate shape by multi-step die-means or the like.

The cast bushing I4 which is to envelop the body metal elements I! andI3 may then be diecast in situ of molten metal difiering from the bodymetal of the container, and preferably having a lower melting point thansaid body metal.

This may be done in any suitable manner, as for example by employing asectional mold having a metal-receiving concavity corresponding to thedesired shape and size of the bushing M. This sectional mold may beapplied to the body metal bordering the opening II, with the elements I2and I3 projecting into the metal-receiving space of the mold. The moltenmetal, at a temperature sumciently high to insure proper fluidity, maythen be poured or forced or injected into said space under highpressure, enveloping the elements I! and I3 and filling all theunoccupied space in said mold. The molten metal is then caused orpermitted to harden, and the sectional mold withdrawn, whereupon thecast bushing I4 is left outlining the container opening; said bushingbeing in continuous intimate contact with the body metal flange l2 andprojections l3, and securely fixed against movement relative thereto.

A suitable low melting point metal composition from which the bushing l4may be cast, may comprise an alloy including approximately to of zinc,about 5% of aluminum, about 1 to 4% of copper, and about 0.1 to .05% ofmagnesium. The foregoing proportions, and also the constituent elementsof the composition, may

be varied or changed in accordance with the different degrees-ofhardness or other qualities desired.

Prior to the application of the mold to the body metal bordering thecontainer opening, the body metal, at least in the zones thereof whichthe molten metal will subsequently come in contact with, is preferablycleaned of any scale or dirt that may be present, so as to improve thecharacter of the union or bond between the'die-cast metal and the bodymetal. If desired, the union or bond may be further improved bypreliminarily coating or plating the container body metal, at least inthe zones to which the molten metal is subsequently to be applied, withcadmium or zinc. In any event, the molten metal upon hardening will becontinuously bonded to the enveloped metal.

The upper or exposed end of the cast bushing l may bear a generallyflat, annular end-surface l8, which is contiguous to and meets theexposed outer surface of the body metal at the meeting or junction zoneII. If desired, this cast'metal surface l8 may extend in directcontinuation of and indeed in the same plane as the adjacent exposed orouter surface of the wall body metal.

The bushing II is preferably cast with a sharply-deflned internalscrew-thread l5 therein, for holding a threaded closure plug. Ifdesired, however, the bushing may have its internal screwthread l5 cuttherein after the bushing has been cast.

A screw-threaded metal closure plug or bung l8 may then bescrew-threadedly engaged with the bushing H, to close the openingoutlined by said bushing. This closure plug l8 may be formed in anysuitable manner, as for example by being cast or pressed into shape. Theexternal thread IQ of this closure plug may either be cast into theplug, or it may be cut into the wall thereof after the plug has beenformed.

The closure plug I8 is preferably provided with a laterally extendingannular flange 20, whose lower surface 2| is in juxtaposition to thebushing end-surface l8 and also overhangs or overlaps the junction zoneI! where the end-surface of the cast metal of the bushing meets theouter surface of the body metal of the container. ,An annular sealinggasket or washer 22, which may be formed of natural or synthetic rubberor of any other suitable gasket material, covers this junction zone l1,and is pressed down tightly thereagainst by the flange-surface 2| whenthe closure plug I8 is screwed tightly into the bushing ll. Thus, asillustratedin Figures 3 and 4, the closure plug l8, when screwed intothe bushing I 4, compresses the sealing gasket or washer 22 forcing ittightly against the junction zone H, with the gasket.material beingtightly pressed against both the cast metal surface [6 radially inwardlyof the junction zone I! and against the adjoining outer surface of thebody metal radially outwardly of the junction l1.

By virtue of the foregoing construction, the washer or gasket 22performs the dual function of sealing against escape of containedliquidor fluid between the engaged plug it and bushing l4, and also ofsealing against escape of liquid or v through the closure means, andprovides an excellent and yet inexpensive fluid-tight seal.

The effectiveness of the fluid-tight seal realizable with the closuremeans of the present in- 5 ventlon'is attributable in large measure tothe continuous close bond between bushing metal and container metal(derived by casting the bushing in situ), coupled with the placement ofgasket 22 over the Junction zone I! so that the same gasket sealsagainst possible leakage not only between closure plug and bushing, butalso between the bushing and the body metal embedded therein.

The closure plug l8 may be recessed as at 22 and inside this recess 23may be disposed a diametrically-extending web of metal 24, preferablyintegral with the plug metal, to provide seizure means whereby theclosure plug I8 may be forcibly tightened or loosened. Thus, the end 01'any suitable tool or implement, as for example a wrench or a pair ofpliers, may be operatively inserted into the plug recess 22 and engagedwith the diametrically-extending metal web 24, and then turned in thedesired direction thereby to loosen or tighten the closure plug as thecase may be. The provision of the recess 23 enables the seizure-means 24to be disposed inside the body of the plug, thereby reducing the extentto which the plug must project beyond the container wall I 0.

It is to be expressly understood that, if desired, other types of bungsor closure plugs may be employed in lieu of the illustrated plug i8.

If desired, tamper-indicating means may be 85 associated with theclosure plug to detect unauthorized opening of the container closuremeans. In Figure 3, the closure plug I8 is shown wire-sealed, with thesealing wire 25 being looped through a hole 26 in the closure plug andan aperture 21 in a lug 28 welded to the container wall I 0. The endportions of the sealing wire 25 are permanently gripped by a lead orother metallic seal 29, thereby making it impossible to rotate theclosure plug l8 without breaking the sealing-wire 25.

In the particular embodiment illustrated in in Figure 4, the closureplug l8 in lieu of being wire-sealed is instead provided with a thinsheetmetal seal cap 30 which may be manually applied thereto. This sealcap 30 may comprise a flat disc end portion adapted to cover theoutermost end of the closure plug l8, and a downtumed peripheral sideflange-portion 3| whose lowermost margin 32 may be turned inwardly andcrimped around the lower edge of a prongbearing strip of metal 33 placedagainst the inner surface of the cap side-wall 3|, thereby permanentlyto retain said strip 33 in position. This inner strip of metal 38 bearsa series of inwardlyextending downwardly-inclined spring prongs 24struck therefrom, the upper ends of which are adapted obstructedly toengage the radially outermost marginal portion of the gasket-compressingplug shoulder 2 I.

The seal cap 30 may be manually snapped onto the closure plug l8, andonce it has been applied thereto it cannot be removed therefrom withoutdestroying or visibly damaging the cap. Thus, once the upper ends of thespring prongs 34 have moved past and cleared the lower corner of theplug-flange 20, they spring radially inwardly into obstructing relationto the shoulder 2|, and thereafter effectively resist all efforts toremove the seal cap without detection.

The seal cap 30 may be peripherally weakened or scored along the corner35, as shown, to facilitate destruction of the cap when it is desired toobtain access to the closure plug l3.

Any attempt to unscrew the closureplug [8 Without r m vin the seal cap30 will be futile, because the cap 30 is loosely rotatable on theclosure plug l8 and will merely rotate freely thereon. Furthermore, ifsubstantial pressure should be applied to the thin sheet-metalcap 30, itwill necessarily become visibly deformed, thus indicating that it hasbeen tampered with.

In Figures and 6, the closure means illustrated in Figure 4 is showncentrally disposed on a transversely-extending end-awl of a cylindricalcontainer. The major plane of this endwall 36 is preferably disposed arelatively substantial distance inwardly of the uppermost transverseedge 4| of the container. The endwall 36 may be peripherally joined tothe container cylindrical side-wall 31 in any suitable manner, as forexample by being peripherally welded thereto, or by having its marginalportion lapped over the marginal portion of the side-wall and thencrimped therewith downwardly and outwardly to form the beaded seam 38.

A portion of end-wall 36 in the vicinity of the container opening,preferably of limited area, may be pressed outwardly as at 39 toprotrude beyond the major plane of end-wall 36, so that theinwardly-extending bushing ll at the opening will not extend inwardlybeyond the major plane of end-wall 36, all as illustrated in Figure 6.By virtue of this construction, the container may be inverted andsubstantially all of its liquid contents drained through the containeropening (shown occupied by the closure plug, in Figure 6), with thedrainage-obstructing effect of bushing l4 being confined to the smallbody of'liquid in the relatively limited trough-like space 40.

By having the major plane of end-wall 36 disposed a relativelysubstantial distance inwardly of the container rim ll, the closure plugl8 will not protrude beyond said rim when engaged in the bushing,notwithstanding the presence of the protuberant zone 33, thus making itpossible for the container to be handled and even inverted withoutdamaging the closure means.

The present invention may be embodied in other specific forms withoutdeparting from the spirit or essential attributes thereof, and it istherefore desired that the present embodiments be considered in allrespects as illustrative and not restrictive, reference being had to theappended claims rather than to the foregoing description to indicate thescope of the invention.

Having thus described the invention, what is hereby claimed as new anddesired to be secured by Letters Patent, is:

1. In a sheet metal container having a relatively small opening formedin a wall thereof, an annular inwardly extending flanged portion at saidopening integral with the wall body metal.

a plurality of peripherally spaced projections formed at the inner endof said annular flanged portion and extending generally perpendicularly6 thereto, a thread-bearing bushing of a. lower melting point metal,pressure-cast in situ, enveloping said flanged portion and saidprojections and outlining said opening, said bushing having an endsurface contiguous to andin substantially 10 direct continuation of theadjacent outer surface of the wall body metal, an annular sealing gasketoverlapping the junction zone of said surfaces. and a screw-threadedclosure plug engaged with said bushing and pressing said gasket tightlyagainst said junction zone.

2. In a sheet metal container having a relatively small opening formedin a wall thereof, an annular inwardly extending flanged portion at saidopening integral with the wall body metal,

said flanged portion having keying means associated therewith, saidkeying means extending generally transversely of said annular flangedportion, a die-cast bushing. cast in situ, enveloping said flangedportion and said keying means and outlining said opening, an annularsealing gasket overlapping the junction between body metal and castmetal, and a closure element firm ly engaged with said bushing andpressing said gasket tightly against said'junction.

3. In a sheet metal container having a relatively small opening formedin a wall thereof, an annular inwardly extending flanged Portion at saidopening integral with the wall body metal, said annular flanged portionhaving a plurality of projections formed integrally therewith andgenerally angularly related thereto, a threadbearing bushing of a lowermelting point metal,

said opening integral with the wall body metal.

a projection formed .at the lower end of said annular flanged portionand extending generally radially therefrom, a thread-bearing bushing ofa lower melting point metal, pressure-cast in situ,

enveloping said flanged portion and outlining said opening, an annularsealing gasket in contact with the outer surface of said body metalalong an annular zone encircling said opening, and a screw-threadedclosure plug engaged with said bushing and pressing said sealing gaskettightly against said outer surface of the body metal.

HOWARD W. DODSON.

ing, an annular sealing gasket overlapping the-

